1. Field of the Invention
This invention relates to high speed, photographic silver halide emulsions and film elements prepared therefrom. Specifically, this invention relates to films with reduced silver halide coating weights and compounds which can be used to reduce fog.
2. Description of the Prior Art
Antifogging compounds useful in silver halide systems are legion in number in the prior art. These compounds are useful in conventional systems sensitized with gold and sulfur compounds, for example. Currently, however, there is a pressing need to reduce silver halide coating weight in order to conserve coats and finite resources. One way of accomplishing this reduction in coating weight is to further sensitize the emulsion in order to raise the speed of the film prepared, using smaller silver halide crystals which give higher covering power but otherwise would have lower speed. Addition of more sensitizer also increases fog. Fog can be reduced by adding more of the conventional antifoggant but these antifoggants also reduce emulsion speed. This is a common problem and one which has bothered the emulsion/film making field for some time.
It is an object of this invention to provide a novel class of compounds particularly useful as antifoggants in silver halide emulsions. It is another object to provide silver halide emulsion antifoggants which are particularly efficacious in high speed, low coating weight film elements made from these emulsions.